Frontal Attachment Device for Syringe with Pinch-Activated Retraction

ABSTRACT

A retractable needle device attachable to the front of a fluid collection or infusion device such as a syringe, the retractable needle device comprising a housing having an engagement member, a slide support surface, a retraction cavity and a first pinch surface; a needle; a needle alignment member comprising a needle tube and a second pinch surface; and a needle retraction mechanism positioned within the needle tube and configured to bias the needle rearwardly; wherein the first and second pinch surfaces are configured so that a pinching force applied to them will cause relative lateral movement between the housing and needle alignment member. This translational movement from an injection position, wherein the needle is aligned with the syringe connector, to a retraction position, wherein the needle is aligned with the retraction cavity, allows the needle retraction mechanism to force the needle into the retraction cavity.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 13/470,855, filed May 14, 2012, which is a continuation of U.S.patent application Ser. No. 12/136,462, filed Jun. 10, 2008, and theportions of those applications that relate to the embodiments of FIGS. 4and 5 as disclosed therein are incorporated by reference into thisapplication. This application is also a continuation-in part of U.S.patent application Ser. No. 13/714,819, filed Dec. 14, 2012.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a newly disclosed frontal attachment having aretractable needle that is attachable to conventional medical devicessuch as syringes. The invention relates more particularly to a medicaldevice comprising in combination a needle, needle positioner, needleretraction mechanism, and a syringe engaging member with a retractiontube. The subject device has a needle retraction mechanism that isactivated by pinching action and retracts the needle from a patient andpropels it into a retraction tube that is part of the hub assembly.

2. Description of Related Art

Conventional syringes comprising a generally cylindrical barrel, a fixedneedle projecting forwardly from the barrel, and a plunger slidablydisposed inside the barrel through an opening in the rear of the barrelare well known. More recently, syringes have been made with a luerconnector on the front of the barrel to which a needle hub is attachableto allow needles of different gauges or sizes to be used with a commonlyconfigured barrel.

Even more recently, in an effort to control the spread of blood-bornepathogens and the incidence of contamination by contact with eitherexposed needles or bodily fluids, syringes having fixed or changeableneedles have been designed to embody various “safety” elements. Such“safety” elements should desirably include a retractable needle, butmany products marketed as having “safety” elements include, for example,covers or guards that are manually operated by medical personneladministering an injection to shield or cover the needle tip followingremoval of the needle from a patient.

Some previously disclosed needle retraction systems without changeableneedles are activated either manually or automatically by application ofa force upon completion of an injection to force the needle and needletip back inside a retraction chamber. The only known syringe having achangeable, retractable needle does not have a conventional luer lockconnection, and the retraction mechanism is activated by the applicationof a forwardly directed force to the plunger handle following removal ofthe needle from a patient, thereby exposing the needle and also exposingthe user to the risk of needle-stick injury.

Although many advancements in syringe technology have been made inrecent years, a frontal attachment device is needed that can be usedwith a standard syringe having a conventional luer lock connector, thatoffers the advantages of a changeable needle in combination with theadvantages of a retractable needle providing sufficient retraction forceto retract the needle while inserted into a patient, and that can beactivated simply and easily by the application of a pinching force.

SUMMARY OF THE INVENTION

A medical device is disclosed that features automated needle retractionwherein needle retraction is initiated by the application of opposedcompressive forces in line with a principal sliding interface to reducethe likelihood of sticking, hang-up or canting that could otherwiseimpede the translational movement of one element of the device relativeto another. As applied to a syringe, the subject medical device furtherincludes an automated retraction device wherein the needle retractionmechanism can be activated independently of the position of the plunger.

A retractable needle device is disclosed that comprises an engagementmember selectively attachable to a cooperatively configured, forwardlyfacing portion of a medical device such as a conventional syringe havinga forwardly facing luer lock connector. Other medical devices with whichthe retractable needle device can be used can include, for example andwithout limitation, other fluid collection or infusion devices that canutilize a retractable needle. In addition to the engagement member, theretractable needle device desirably comprises a retraction tube, aneedle alignment member comprising a needle tube, a rearwardly-biasedneedle retraction mechanism seated inside the needle tube, a retractableneedle projecting forwardly of the needle alignment member, and a fluidflow path from the fluid chamber through the engagement member, needletube, needle retraction mechanism and needle, wherein the needle isretracted following use into the retraction tube applying a pinchingforce. As used throughout this disclosure, the terms “attachable,”“detachable” and “changeable” are generally used to characterize frontalattachments, such as needles or needle/hub combinations, that areselectively attachable to, detachable from, or otherwise changeable inrelation to a medical device such as a syringe for purposes such as,without limitation, selecting a particular gauge needle for a particularclinical use.

If desired, a retractable needle device as disclosed here can also bemade with a slip-fit luer cone, snap-on or other attachment mechanisminstead of a conventional luer lock connector provided that the medicaldevice with which it is used is cooperatively configured. A retractableneedle device as disclosed here desirably comprises a needle that isretractable, and retraction is activated by pinching pressure appliedgenerally perpendicularly to the longitudinal axis through the needle. Asatisfactory retractable needle device as disclosed here desirably hassufficient retraction force to retract a needle that is still insertedinto a patient's body and thereby prevents exposure of the contaminatedneedle to others. A retractable needle device as disclosed heredesirably utilizes a retraction tube that is not embodied, for example,in a syringe barrel or plunger handle, and is instead part of anattachable assembly.

Following an injection using a medical device provided with the medicaldevice disclosed here, a clinician administering the injection desirablyapplies digital pressure to two opposed textured tabs with a thumb and afinger. Application of pinching pressure causes relative motion of theneedle holder and needle away from the syringe connector and toward theretraction tube. This relative motion is continued until the needleholder is aligned with a forwardly facing opening of the retractiontube, at which point the needle retraction mechanism propels the needleholder into the retraction tube. The needle holder carries the attachedneedle rearwardly to a fully retracted position where the needle isreleased from the patient and the needle tip no longer projectsforwardly from the needle tube. Also, using the device disclosed here,if a clinician administering an injection needs or decides to terminatethe injection, the needle can be retracted to prior to infusing all thefluid in a syringe.

BRIEF DESCRIPTION OF THE DRAWINGS

The apparatus of the invention is further described and explained inrelation to the following drawings wherein:

FIG. 1 is a side elevation view of one embodiment of a syringe with anattached retractable needle device;

FIG. 2 is a cross-sectional view of the apparatus of FIG. 1 taken alongline 2-2 of FIG. 1;

FIG. 3 is an exploded view of the retractable needle device of FIG. 1.

FIG. 4 is a perspective view illustrating cooperation of a syringeconnector of a retractable needle device with a luer lock connection ofa syringe barrel.

FIG. 5 shows the syringe and retractable needle device of FIG. 1 aftersyringe plunger has been fully depressed.

FIG. 6 is a perspective view of a retractable needle device beingactivated by a user.

FIG. 7 is a perspective view of a retractable needle device prior toretraction of the needle.

FIG. 8 is a perspective view of a retractable needle device afterretraction of the needle.

FIG. 9 is an elevation view of the retractable needle device of FIG. 8.

FIG. 10 is a cross-section view of the retractable needle device of FIG.9 taken along line 10-10.

FIG. 11 is an elevation view of the device as in FIG. 1 with a needlecover installed.

FIG. 12 is a cross-sectional view of the device of FIG. 1.

Like reference numerals are used to describe like features in allFigures of the drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

For illustrative purposes, the retractable needle device of theinvention is described below in relation to a medical device that is asyringe assembly onto which a retractable needle device of the inventionhas been releasably installed. It should be appreciated, however, thatthe retractable needle device of the invention is similarly useful forcollecting or infusing fluids with other medical devices that are notsyringes.

FIGS. 1, 2 and 4 depict a syringe assembly 10 comprising syringe barrel20, having a luer lock connector 22, 23 disposed at the front end and aplunger handle 26 with plunger seal 28 slidably engaging the inside wallof syringe barrel 20, and a retractable needle device 30 attached toluer lock connector 22, 23 so as to establish fluid communicationbetween fluid chamber 24 of syringe barrel 20 and needle 32 ofretractable needle device 30. Plunger handle 26 extends rearwardly froman opening in the back of syringe barrel 20 and is shown positioned asit could be prior to the injection of a fluid disposed inside fluidchamber 24 into a patient (not shown) if tip 34 of needle 32 wereinserted into the patient, recognizing that the position of plunger seal28 relative to syringe barrel 20 will depend upon the amount of fluidthat is drawn into fluid chamber 24. An injection force is applied to afluid disposed inside fluid chamber 24 through plunger handle 26 bydepressing thumb cap 27 of plunger handle 26 while stabilizing syringebarrel 20 by applying oppositely directed finger force to the forwardlyfacing surfaces of outwardly projecting flanges 29.

FIG. 3 is an exploded view of retractable needle device 30 furtherillustrating its components. Housing 36 preferably comprises first pinchtab 35, luer lock tube 38, slide support surface 41, and retraction tube42. Connector tube 38 is desirably configured to form a fluid tight sealbetween luer lock connector 22 of syringe barrel 20 and needle holder46. Fluid seal 44 desirably comprises an elastomeric material and atleast a portion of fluid seal 44 is positioned within an annular recess49 defined in forwardly facing slide support surface 41. Fluid seal 44provides a fluid seal between housing 36 or luer tip 22 and needleholder 46. First pinch tab 35 preferably comprises ridges or othertexture to provide slip resistance when gripped with a finger or thumb.

Forward of fluid seal 44 is needle holder 46, which is attached toneedle 32. Needle holder 46 comprises an axial bore through a generallycylindrical elongate body 45 and larger diameter head 47. Body 45 ispreferably slightly longer than needle tube 54. Retraction spring 48 ispositioned around body 45 and is compressed between an annular ledgeinside the front end of needle tube 54 and a forwardly facing annularshoulder between body 45 and head 47. Prior to needle retraction,retraction spring 48 is under compression and biases needle holder 46and needle 32 rearwardly relative to needle tube 54 and housing 36.

Retractable needle device 30 also comprises needle alignment member 52.Needle alignment member 52 comprises a rearwardly facing surface thatslidably engages forwardly facing sliding surface 41 of housing 36, andfurther comprises forwardly projecting needle tube 54 and second pinchtab 56. Second pinch tab 56 is desirably positioned on an opposing sideof syringe barrel 20 from first pinch tab 35. Second pinch tab 56 ispreferably textured similarly to first pinch tab 35. A retainer clip 58comprises a hole 62 configured to engage needle tube 54. Retainer clip58 also comprises retaining brackets 64 configured to retain needlealignment member 52 against housing 36, while allowing sliding motionbetween them when a sufficient pinching force is applied to first andsecond pinch tabs 35, 36.

As shown in FIG. 4, tapered luer cone member 22 comprising asubstantially cylindrical bore cooperates with annular collar 25 havinginternal threads 23 disposed in spaced-apart relation to tapered luercone member 22 to form a luer lock connector that is engageable withlocking wedges 66 of housing 36 to provide a fluid-tight seal betweenhousing 36 and syringe barrel 20 whenever needle tube 54 is coaxiallyaligned with barrel 20. When syringe assembly 10 is assembled as shownin FIG. 1, a continuous fluid flow path is formed from fluid chamber 24(FIG. 2) through housing 36, fluid seal 44 and needle holder 46 toneedle 32.

Operation of the syringe assembly 10 during filling and injection issimilar to many existing syringe and needle systems and will be readilyunderstood by those of ordinary skill in the art. Referring to FIG. 5,syringe assembly 10 is shown with plunger handle 26 advanced relative tosyringe barrel 20 to the point it will be following an injection, whenplunger seal 28 has forced the fluid out of fluid chamber 24. This isthe position in which plunger handle 26 will desirably remain relativeto syringe barrel 20 during activation of the retractable needle device30. Following an injection, the clinician administering the injectioncan retract needle 32 by pinching first pinch tab 35 toward second pinchtab 56, as illustrated in FIG. 6.

FIGS. 7 and 8 illustrate an assembled retractable needle device 30before (FIG. 7) and after (FIG. 8) needle 32 has retracted. In FIG. 7 aforward end of needle holder 46 protrudes slightly beyond the front endof needle tube 54. In FIG. 8, needle 32 and needle holder 46 have beenretracted into retraction tube 42 and are no longer visible. FIG. 9 isan elevation view of the retractable needle device 30, in retractedposition, of FIG. 8. FIG. 10 is cross-section view of the sameretractable needle device 30, illustrating the arrangement of needle 32and needle holder 46 after retraction of needle 32.

FIGS. 11 and 12 illustrate elevation and rotated cross-sectional viewsof the assembled device as in FIG. 1, but with a needle cap 70 installedto protect the needle from damage or contamination prior to use of thedevice. In FIG. 12, a laterally projecting tab 72, 74 is visible thatengages the inwardly facing side of pinch tab 56 to restrict relativemovement and premature needle retraction while needle cap 70 is inplace.

Syringe engaging member 36, needle holder 46, needle alignment member52, syringe barrel 20 and plunger handle 26 are all desirably moldablefrom a suitable moldable polymeric material. Such materials and moldingmethods are believed to be well known to those of ordinary skill in theart. Similarly, it will be appreciated by those of skill in the art ofsyringe design and manufacture that a medical device such as retractableneedle device 30 disclosed here can be used with syringes that areeither pre-filled or not, and that can comprise component portions madeof glass or other suitable materials for particular applications.Similarly, it will be appreciated that fluid seal 44 and plunger seal 28are desirably made of a rubbery or elastomeric polymeric material of thetypes commonly known for use in such medical applications. Similarly, itwill be appreciated that materials used in the fabrication of this andother medical devices must be approved by the relevant regulatoryauthorities for use in such devices. Needle 32 as disclosed is desirablymade of stainless steel and retraction spring 44 can be made ofstainless steel or any other similarly effective medical grade material.

Other alterations and modifications of the invention will likewisebecome apparent to those of ordinary skill in the art upon reading thisspecification in view of the accompanying drawings, and it is intendedthat the scope of the invention disclosed herein be limited only by thebroadest interpretation of the appended claims to which the inventorsare legally entitled.

We claim:
 1. A retractable needle device selectively attachable to a fluid collection or infusion device having a forwardly facing connector, the retractable needle device comprising: a housing having a rearwardly facing engagement member attachable to the forwardly facing connector, a forwardly facing slide support surface having a first opening in fluid communication with the engagement member and a second opening laterally spaced apart from the first opening, the second opening communicating with a rearwardly projecting needle retraction cavity, a first pinch surface, and a fluid path between the engagement member and the first opening; a needle; a needle alignment member comprising a needle tube and a second pinch surface; a needle retraction mechanism comprising a needle holder, the needle holder positioned within the needle tube and configured to bias the needle rearwardly; and an annular fluid seal seated in the first opening and providing fluid communication between the housing and the needle holder; wherein the first and second pinch surfaces are configured so that a pinching force applied between them will cause the housing to move laterally in relation to the needle alignment member from a first position, wherein the needle is aligned with the first opening, to a second position, wherein the needle is aligned with the second opening so that the needle retraction mechanism biases the needle into the retraction cavity.
 2. The retractable needle device of claim 1 further comprising a retainer clip configured to retain the needle alignment member adjacent to the slide support surface of the syringe engaging member.
 3. The retractable needle device of claim 2 wherein the retainer clip comprises a forward surface, a hole defined in the forward surface configured to surround the needle tube, and one or more tabs configured to extend at least partially behind the slide support surface.
 4. The retractable needle device of claim 2 wherein the retainer clip is configured to engage at least a portion of the needle alignment member.
 5. The retractable needle device of claim 1 wherein the engagement member comprises a portion of a luer lock connector.
 6. The retractable needle device of claim 5 wherein the engagement member comprises a plurality of spaced-apart, radially-projecting wedges configured to engage a threaded collar projecting forwardly from the fluid collection or infusion device.
 7. The retractable needle device of claim 1 further wherein the fluid collection or infusion device is a syringe.
 8. The retractable needle device of claim 1 wherein the fluid seal is seated at least partially inside an annular recess inside the first opening.
 9. The retractable needle device of claim 1 wherein the fluid seal comprises a fluid flow path that is coaxially aligned with the needle holder prior to needle retraction.
 10. The retractable needle device of claim 1 wherein the needle retraction mechanism further comprises a compression spring.
 11. The retractable needle device of claim 10 wherein the needle holder is biased against the slide support surface whenever the housing is disposed between the first and second positions.
 13. The retractable needle device of claim 1 wherein a portion of the needle holder projects forwardly from the needle tube.
 14. The retractable needle device of claim 10 further comprising an annular surface at a front end of the needle tube and an annular shoulder defined on the needle holder and wherein the spring is compressed between the annular surface and the annular shoulder when the housing is in the first position.
 15. The retractable needle device of claim 1 wherein the first and second pinch tabs are textured to improve user grip.
 16. The retractable needle device of claim 1 wherein the needle alignment member and the syringe engaging member are each made of moldable polymeric material.
 17. The retractable needle device of claim 7 configured for use with a syringe having a glass barrel.
 18. The retractable needle device of claim 7 configured for use with a syringe having a plastic barrel.
 19. The retractable needle device of claim 7 configured for use with a prefilled syringe.
 20. The retractable needle device of claim 1 wherein the needle retraction mechanism provides a retraction force upon activation that is sufficient to retract the needle directly from a patient into which the needle is inserted at the time of retraction.
 21. The retractable needle device of claim 1 in combination with a fluid collection or infusion device.
 22. The retractable needle device of claim 1 in combination with a needle cap. 